©Lorne Gill/NatureScot/David Colthart
Report prepared by: Andrew Kent, NatureScot Sea Eagle Management Team
Following consultation with Local Sea Eagle Stakeholder Groups, the Sea Eagle Management Scheme (SEMS) was revised for 2020 onwards.
The revised SEMS has taken account of feedback from farming and crofting representatives on these Groups and now offers a wider range of management measures and increased flexibility to those who are experiencing issues with white-tailed eagle (WTE) predation of livestock.
One of the new measures included in the revised SEMS is enhanced shepherding. This measure was developed following on from monitor farm work and initial shepherding work carried out at Sheep Stock Club (SSC) A in 2019, which recorded WTE activity on the hill and possible signs of predation.
A suggested methodology for this new measure was developed with advice from SEMS call off contractors who had delivered similar work on NatureScot Monitor Farms. The measure has been targeted at farmers and crofters managing sheep flocks on more extensive areas and in 2020 had two main aims:
- Allow more detailed information on WTE interactions with sheep flocks to be recorded and reported back to NatureScot from the shepherded areas.
- Provide a scaring element through the additional presence of shepherds on areas of the hill.
Shepherds are asked to record information on a range of variables – e.g. weather, WTE activity, possible signs of predation, presence/absence of prey and other predator species and feed this information back to call off contractors and NatureScot.
This information will be used to help inform future management on the individual holdings, to try and address issues being reported with WTEs and hopefully allow identification of specific areas which might be experiencing more problems with WTEs than others. In addition, feedback from shepherds delivering the measure will also help refine this SEMS option, to improve its future effectiveness.
It was hoped, due to experience with observers on monitor farms that the additional presence of shepherds on the hill would also act as a visible deterrent to WTE interaction with livestock in parts of the holdings where this measure was implemented.
In 2020 four farms in Argyll – Farms A and Farm B and three SSCs on the Isle of Skye – SSC A, B and C participated in the trialling of this measure with support from the SEMS.
The SEMS paid an hourly rate of £12.80 for the delivery of this work. This rate was calculated based on averages taken from the SAC Consulting Farm Management Handbook.
In their applications to the SEMS, each participating farm and SSC outlined the number of hours they would like to commit to this measure in 2020. The measure was targeted at the key lambing and post-lambing period when lambs are at greatest risk to WTE predation.
The shepherds participating were provided with an information pack in electronic or hard copy format before the commencement of the measure. This information pack outlined the requirements of the work and contained templates, maps and eagle ID cards for guidance and recording purposes.
Each participating farm and SSC also received support from one or more SEMS call off contractors. Andrew Kent liaised with the shepherds or the SSC clerks and farmers co-ordinating this work and provided assistance and advice when required.
For Farms A in Argyll, a WhatsApp support group was also setup which included the shepherds delivering and overseeing the work, a SEMS call off contractor and Andrew Kent. As well as an additional support mechanism, relevant information including photos, videos and map screenshots were shared in this group, further improving communication.
The initial plan was for each participating holding to have an on-site introductory session with their SEMS call off contractor(s), including some practical time spent on the hill answering any questions and completing some trial runs of data collection. Covid-19 and associated lockdown restrictions meant that only SSC C were able to have an on-site visit prior to lockdown with their call off contractors.
This was not ideal, however SEMS call off contractors and Andrew Kent were accessible remotely via email and phone to provide support and ensure ongoing liaison through the season. At the end of the season, a collaborative case study report was produced for each individual participating holding based on the data collected, which will act as a baseline for future work.
The purpose of this summary report is to provide an overview of the work carried out on the participating holdings in 2020, including feedback and suggestions from those delivering and co-ordinating the measure. An assessment of the effectiveness of enhanced shepherding in 2020 and potential areas for further research, based on observations from the participating holdings is also included.
Overview of participating holdings
The seven holdings delivering this work in 2020 all comprise significant areas of extensive open hill, with ewes either lambed on the hill, or ewes and lambs turned out there shortly after lambing indoors, on in-bye or in hill parks. For the purposes of this report, three farms in mainland Argyll have been considered as one larger unit, Farms A, with the labour involved in this work shared.
Table 1 below provides an overview of the scale of the participating holdings, the flock size and the lambing locations of each. Figure 1 below provides an overview of the landscape that some of the participating holdings are working in.
|Holding||Holding size (ha||Flock numbers||Lambing location|
|Farms A||1962 ha||940 breeding ewes and gimmers||In-bye and hill parks|
|SSC A||1338 ha||1350 breeding ewes and gimmers||Hill|
|Farm B||1283 ha||838 breeding ewes and gimmers||In-bye and hill|
|SSC B||2800 ha||990 breeding ewes and gimmers||Hill|
|SSC C||1800 ha||850 breeding ewes and gimmers||Indoor and hill|
Figure 1: Overview of the landscape on some of the enhanced shepherding areas.
Clockwise from top left: Farms A, SSC A, SSC C and Farm B
Whilst the individual management systems on each of these areas are not identical, all of the participating holdings comprise traditional hefted flocks, which rely on the recruitment of suitable replacement stock from within the flock. All of the holdings have been involved in the SEMS for a number of years and have reported ongoing predation of lambs from WTEs.
The levels of reported loss from WTE on each of these areas and in individual years differs. However, all have reported that the presence of WTE has resulted in additional lamb losses, over and above expected levels, which is having a negative impact on the availability of replacement stock, which each of these holdings rely on.
In 2020 twelve shepherds were supported by the SEMS to gather more detailed information on WTE interactions with sheep flocks on these holdings as well as to try and provide a scaring element through their presence on the hill. A summary of the key findings from these holdings in 2020 is detailed below.
Shepherds delivering the measure in 2020 were asked to record observations of WTE on their holdings and where possible record information on the age class of birds observed, whether they were alone or part of a group and any behaviours of note or interactions with their flock.
In 2020, 141 observations of WTE over the participating holdings were recorded. The highest number of observations were recorded on SSC A (52), followed by Farms A (43), Farm B (37), SSC B (5) and SSC C (4). The majority of the recorded observations were of sub-adult or juvenile birds (84), with 30 recorded observations of birds whose age class was not known or recorded and 27 recorded observations of adult WTE.
Figure 2: Adult WTE photographed over Farms A ©Will Currie
A key aim of the enhanced shepherding work was to determine whether the shepherd’s presence on the hill acted as a deterrent to interaction with the flock. At SSC A, the shepherd there, recorded a couple of occasions where his presence could be considered as deterring WTE activity around new-born lambs and possibly preventing predation of these lambs by WTE.
On the 8th of May, it was noted in the end of day summary that the shepherd had come across a WTE “sat on a rock above lambing ewes that took off and flew south” possibly as a result of his presence. On the 21st of May, the shepherd at SSC A noted that:
“There was a ewe with a lamb that hadn’t been long born and two WTEs sitting on the ground on either side of her, possibly trying to intimidate her…they took off and re-joined the WTE circling above”
As well as indicating that the shepherd’s presence could have encouraged WTE to move off, these observations also highlight that WTE at SSC A were showing interest in newly born lambs. At SSC C, overall feedback on the measure in deterring WTE interaction with the flock was positive:
“Having extra bodies out on the hill seems to have had the desired effect of increasing viable lambs and keeping the eagle presence at bay.”
Whilst there were positive signs from observations and feedback from SSC A and SSC C, this effect was not experienced on other holdings, as feedback from the shepherd at Farm B highlighted:
“Human presence made no difference to the behaviour of the birds – although at times they seemed curious and followed the quad.”
“During gathering, one juvenile WTE came down to the hill park with the sheep and sat on the fence post watching. Up until that point there had been no sightings of a WTE down as low as the hill parks, suggesting they are following the sheep movements.”
Whilst the measure did not have the desired effect of deterring WTE presence at Farm B, this feedback in itself is useful. At all of the holdings, the data collected on WTE activity has also allowed an identification of areas of the hill where WTE activity was focused in 2020.
On some of the holdings, feedback suggests that whilst the enhanced shepherding measure helped reduce WTE activity and potential lamb predation on the areas where it took place, shepherds felt that WTE activity had been pushed on to other areas. The following feedback from Farms A and SSC A outlined this:
“Areas that weren’t part of the shepherding work had a relatively high number of pluckings and carcasses compared to the low number of sheep”
“The Enhanced Shepherding has certainly helped this season but with several different hirsels and 1400 plus hectares to cover I feel the WTE adapted their habits to avoid human presence. Where possible, for the future you would need to have shepherds (or presence) continually in the lambing areas to deter the birds and with several lambing areas this cost would be prohibitive to the farm unless fully aided by the scheme.” – Farms A
“Levels of loss on enhanced shepherded areas were low but greater losses were experienced on another area of the common…The enhanced shepherding is useful but the shareholders are concerned that it has caused greater predation of lambs on another heft where the best stock ewes are.” SSC A
Again this feedback from participants is useful and whilst there are positives in terms of the measure seeming to have an effect on WTE activity, further work is needed. This will be considered as part of the review of the measure going forward to try and improve its effectiveness, taking into account the comments from both Argyll and Skye that shepherd’s presence pushed WTEs on to other areas.
Other predator and prey species
Shepherds were asked to record other potential predators of lambs and their signs when delivering this measure as well as recording observations of other WTE prey species. Red fox, golden eagle, ravens and hooded crows were recorded as other potential predators of lambs present on some or all of the participating holdings in 2020, with records of known losses to foxes kept for some of the holdings. At all of the holdings fox control is carried out with records provided on the number of foxes controlled in 2020.
Across all of the holdings, there were very few observations of other WTE prey species recorded. Whilst this may be down to under recording, feedback from the majority of these holdings suggests that prey availability on these areas is depleted, or that prey species which were once formally present, such as rabbits or hares, are now absent. It is recommended that this aspect is investigated further, through targeted survey work. The lack of other prey species or reported declines in these areas could be a significant factor in the ongoing issue of WTE predation of lambs being reported on all of these holdings.
Possible signs of predation
Shepherds were asked to record any lamb carcasses and possible signs of predation when delivering this work and where possible, provide photographs of these sites. In 2020, across the holdings, 31 sites where lamb remains were found were recorded. Whilst on the majority of shepherding days lamb remains were not found, in an extensive open hill system locating remains is more challenging than in an in-bye or hill park setting and it is likely that a number of lamb remains were not found in these extensive areas.
The remains found at each of these sites differed and in some cases it was possible to identify signs which pointed to predation and/or scavenging by a particular predator such as foxes or corvids. WTE activity, in some cases, was recorded at or near these lamb remains sites by shepherds. At a number of sites signs of plucked wool were found, indicating that predation and/or scavenging had taken place at a carcass by a predator. At some sites there were signs of fresh or recently dried blood indicating that predation was a likely cause of lamb death. Figure 2 below outlines some of the lamb remains found at these sites:
Figure 2: Photographs of some of the lamb remains sites recorded in 2020
Levels of lamb loss in 2020
One of the requirements of the enhanced shepherding measure is the completion of an end of season report. This report collates 2020 lambing data from those Farms and SSCs who participated in the trialling of this measure in its first year. A summary of lambing performance and losses between key stages in 2020 on areas where this information is available is detailed in Table 2 below:
|Holding||Expected lambs from scanning||Lambs present at marking (% age loss scanning -marking)||Lambs weaned (% age loss marking – weaning)|
|Farms A||6121||7952||700 (11.9%)|
|SSC A||n/a||1022||944 (7.6%)|
|Farm B||579||375 (35.2%)||337 (10.1%)|
|SSC C||851||637 (25.1%)||579 (9.1%)|
1 On Farms A it was not possible to scan the whole flock in 2020 and the expected lambs figure is only for the individuals in the flock which were scanned.
2 This figure takes account of 85 marked lambs from areas which weren’t scanned hence why it is higher than 1
From Table 2 it is clear that lamb losses on both Farm B and SSC C were significantly higher in the scanning to marking period than the marking to weaning period. This is to be expected given that lambs in the period from birth to marking are more susceptible to the range of factors affecting loss, including predation.
Weather conditions during lambing in 2020 were favourable with some warmer weather and very little in terms of prolonged periods of rain. Lambs would have benefitted from this and losses to exposure would likely be minimal as a result of the good weather during lambing. Many farmers and crofters on the west coast commented that it had been the best weather for lambing for many years and that they had excellent results.
Despite the favourable conditions, significant losses were still experienced on the participating farms over and above expected levels of black loss. An example of this is on Farm B, during the scanning-marking period, with feedback from the farmers there stating that:
“We would expect to be losing between 10-15% lambs on the hill (closer to 10% this year given the good weather) but our figures demonstrate, on average, 35% loss.”
It is difficult to assess the exact level of lamb loss that can be attributed to WTE predation on each of these areas. Whilst not all of these losses are being attributed to WTEs by each holding there are, in some places, patterns which have developed that have coincided with the arrival of WTE on these areas. This is evident in lambing records from Farm B detailed in Figure 3 below:
Figure 3 clearly demonstrates a significant increase in the percentage lamb loss between marking and weaning, which coincides with the arrival of WTE on the Farm in 2013. Between 2010 and 2012 percentage losses in this period were on average 1.7%. Since the arrival of WTE in 2013, the average percentage loss in the, albeit longer, period between 2013 and 2019 is 14.1%.
The Farmer feels that WTEs have a significant role in the increased lamb losses being experienced, especially in this period, where losses historically weren’t a significant issue. This is one of the reasons that the enhanced shepherding measure was trialled here initially, with further work ongoing to try and understand the role of WTE in the significant losses being experienced.
Conclusions and recommendations
Whilst in some cases such as Farm B, the two main aims of the measure were not achieved, there were positives in that the data gathered has allowed a better understanding of WTE activity on these areas, with baseline information now available to inform future work. All of the holdings that participated in the trial in 2020 have reapplied to continue this work in 2021. The measure will be adapted based on feedback from 2020 and in some cases supported by NatureScot observers, to increase human presence on these areas and collect further data.
Feedback from SSC B and C also suggested that the measure had wider benefits than those related to the initial aims:
“Enhanced shepherding helped stimulate discussion about the use of different flock management strategies. We were on this course but the increased focus from the scheme has provided a greater understanding and a more strategic long term view. The support and assistance of call off contractor’s expertise in the field was of great benefit” – SSC B
“The requirement to provide accurate data for the WTE scheme has put a focus on our own need to collect data and the value it has in managing our flock. This is perhaps an unexpected benefit of being part of the scheme as it adds rigour to our management practice and will hopefully benefit the health of the flock regardless of WTE predation.” – SSC C
This feedback is encouraging and hopefully helps to demonstrate the value of the collection of flock management data in trying to better understand the role of WTEs in losses being reported from these areas.
It is recommended that alongside the work being carried out by shepherds to collect and record additional data, NatureScot expands on the initial collection of data relevant to this work. In 2020, productivity of WTE pairs relevant to these areas was assessed where possible and prey remains analysis was carried out on one relevant nest. Whilst prey remains analysis does have its limitations, it does provide an indication of the diet of relevant pairs and where possible, it is hoped that this work can be expanded in 2020.
NatureScot call off contractors checking productivity of WTE © C McIntyre
Further work to investigate prey species availability on these areas is recommended in 2021 to try to understand whether this is a significant factor in the losses being reported from WTEs.
Work is ongoing to refine and standardise the recording and reporting elements of the enhanced shepherding measure for 2021, taking on feedback from shepherds who delivered this work. This should streamline these elements in a way that also allows for enhanced data to be recorded and reported on.
It is hoped that through the continuing ongoing collaborative work related to this measure, the data it is collecting and outputs will improve in 2021 and the significant lamb loss issues which continue to be experienced on these areas can be addressed through this continuing collaborative work.
NatureScot acknowledges and thanks the shepherds, SSC clerks and farmers delivering and co-ordinating this work for their contributions and communication throughout and after the shepherding period. Thanks also go to the NatureScot call off contractors and observers for providing advice and assistance in the delivery of this work, including associated monitoring and liaison work.
Black loss – The unexplained loss of lambs which are missing after accounting for those which are known to be dead.
Heft/Hirsel – An area of the hill where a flock of sheep graze and return to following gathers. Hefting is the sheep’s natural instinct to return to and use that area which it learns from its mother and is passed on through the generations.
Hill park – A fenced area of grazing on the hill, adjacent to a larger area of fenced or unfenced rough grazing. Hill parks are often the interface between the in-bye and open hill.
In-bye – Enclosed improved fields which are often used for lambing or silage production.
Marking – This usually takes place when lambs are 4-6 weeks old. The ewes and lambs will be gathered and marked so that ownership can be identified in areas where there are open marches with other holdings. Lambs will be earmarked to identify each individual in the flock with relevant flock treatments also applied at this time.
Scanning – Ultra-sound scanning of ewes to determine pregnancy status which allows separation of the flock into different groups and areas and a calculation of the number of expected lambs. Scanning usually takes place in February or early March depending on the timing of lambing.
Weaning – The separation of lambs from ewes. The flock will be gathered usually in August or September and lambs will be separated and sorted, with individuals that are to be retained for future breeding identified.